露天矿硐室爆破设计
Blast design for open-pit mines is an important factor for achieving desired mine production and safety results. Good blast design and careful planning are essential for successful Explosives blasting in open pit mines, and should be designed to meet the desired performance requirements. This article will discuss the fundamentals of blast design and provide an overview of the important elements that must be considered when designing a blast.
The blast design process begins with the establishment of objectives, which typically centre around maximising fragmentation, minimising dust, limiting fly-rock (uncontrolled movement of material outside the blast area), and controlling the seismicity caused by the blast. Site specific design criteria such as bench geometries, blasting restrictions, or other special considerations are also taken into account.
The blast design process is a complex one, however the two primary components of the design that must be considered are:
• Blast Patterns: the geometric arrangement of explosive charges used to break up material. This includes the pattern type (staggered, fan, corridor, etc.), the number of holes, their spacing and orientation, and their sizes.
• Explosive Loading: the total amount of explosives used (kg/m3) and the loading configuration (how the explosives are arranged within a single blast hole).
When designing a blast for open pit mines, there are several factors to consider. The geological characteristics of the material being blasted, the size of blocks being targeted, the depth of the benches, and the blasting restrictions in the region should be taken into account.
In terms of blast patterns, a variety of patterns can be used depending on the desired results and the characteristics of the material being blasted. For example, fan patterns are typically used to break up bulk material into smaller fragments, while staggered patterns are used to separate large blocks into more manageable fragments. The number of blast holes, their spacing, and their sizes also affect the blasting results, and should be designed to match the desired results.
The loading of explosives is an important part of the blast design process. The type, size, and quantity of explosives used for a given area will depend on the type and size of material to be blasted. In general, the total quantity of explosives used should be no more than necessary to achieve the desired results. Loading too much explosive can lead to excessive dust and fly-rock, so it is important to match the loading to the desired outcome.
In terms of other components of the blast design process, it is important to consider seismic considerations and any potential nuisance issues. Seismic considerations should be reviewed to determine if blasting can take place safely, as well as to find an acceptable level of vibration that can be tolerated. Nuisance issues such as dust, fly-rock, and noise can be assessed through various methods such as sound intensity monitoring and dust monitoring.
In conclusion, blast design for open-pit mines is a complex process. Various factors need to be taken into account to ensure successful blasting results, including the geological characteristics of the material being blasted, the size of blocks targeted, the depth of the benches, the blasting restrictions, pattern design, and explosive loading. When all of these considerations are taken into account, it is possible to design an effective blast that maximises fragmentation, minimises dust, and limits fly-rock while controlling the seismicity caused by the explosive blast.
